Control apparatus



Jan. 21, 1969 c. H. WALDHAUER, JR 3,

CONTROL APPARATUS Filed May 12, 1965 Sheet of 2 TARGET INVENTOR.

CHARLES H. WALDHAUER R.

ATTORNEY J 1969 c. H. WALDHAUER, JR 3,

CONTROL APPARATUS Filed May 12, 1965 Sheet 2 of 2 FIGB I NVENTOR.

CHARLES H. WALDHAUER JR.

ATTORNEY Patented Jan. 21, 1969 3,422,548 CONTROL APPARATUS Charles H.Waldhauer, Jr., Glendora, Calif., assignor to Honeywell Inc., acorporation of Delaware Filed May 12. 1965, Ser. No. 455,199 U.S. Cl.35--25 6 Claims Int. Cl. F41g 3/26; G01j 1/20; A63f 9/02 ABSTRACT OF THEDISCLOSURE An aiming evaluation device wherein a rotating perforateddisc is positioned at the focal plane of a target viewing optical systemto modulate the received target radiation in accordance with how closelythe optical system aligned with the target. An internally reflectinghollow cone gathers the modulated radiation onto a single detector.

The present invention pertains to aiming evaluation a tarket seekingcapability it is only necessary to aim it' into a generally correctpath. The present invention is ideally suited for this purpose providingdetection of four distinct aiming modes in a relatively inexpensivemanner. An optical system is utilized whose optical axis issubstantially parallel with the direction of fire of the weapon.Infrared radiation emitted from the target, which may be an airplane, isfocused at a focal plane. A mask -is positioned'in this focal plane sothat a small hole in the mask will allow the focused infrared image topass through if the optical axis of the system and consequently theweapon is directly aligned with the target. In the preferred embodimentthree other holes are formed in the mask at positions which will allowthe infrared image to pass through the mask if the weapon is properlyaimed in a compensating manner. For example, if the weapon should beaimed slightly above the target so as to com: pensate for a drop in thetrajectory a hole may be provided in the mask at the position the imagewould be tocuscd when the weapon is accordingly aimed.'Also, holes areused which are representative of an aiming prht which is above and tothe left and above and to the right of the target. In the preferredembodiment a single i1- frared radiation detector is used to senseradiation passing through all four of these holes and a chopper isinserted into the system in such a way as to sequentially chop each ofthe holes so that it can be determined which hole the radiation ispassing through.

It is an object, then, of the present invention to provide apparatuswhich will indicate if a weapon is properly aimed both when the weaponis pointed directly at the target and when the weapon is pointed at somepredetermined compensating distance from the target. Further objects andadvantages will become apparent in the following description anddrawings in which:

FIGURE 1 is a schematic drawing of some of the major components of myinvention showing the principles of operation;

FIGURE 2 is an enlarged drawing showing the chopper and mask of FIGURE1; and

FIGURE 3 is a diagram of the preferred embodiment of the presentinvention in an operable configuration.

Referring to FIGURE 1 a lens 10 is shown which focuses an image of atarget 12 onto a mask 14. Mask 14 is positioned substantially at thefocal plane of lens 10 and has a hole 16 in it at a position suitable toaccept the image of the target when the system is properly aligned on adirect line with the target. In FIGURE 1 target 12 is shown as anairplane and, thus, it may also be desirable to aim the weapon above thetarget 12 and also to the left of target 12 so as to compensate for thecurve of the trajectory and the targets motion. Consequently, a hole 18is provided in mask 14 which will pass the image of the airplane throughif the system is aimed at a point which is the proper distance above andto the left of target 12. If the trainee aims above and to the right ofthe target the image will pass through hole 20, whereas, if the traineeaims simply above the target by a proper predetermined amount the imagewill pass through hole 22. Infrared energy passing through any of thefour holes is collected by an internally reflecting cone 24 and directedto a detector 26. The signal from detector 26 is amplified by anamplifier 28 and presented to logic circuitry 30 where an evaluation maybe made as to whether or not the device was properly aimed. Although thepreferred embodiment operates with infrared radiation it shoud beunderstood that visible radiation such as from a rocket flame orultraviolet radiation will work also.

In order to differentiate between the four holes a chopper 32 isemployed in the optical system to sequentially chop each hole. Chopper32 has four sets of chopping holes, each extending over of the chopperwheel, one set for each hole, which cause an AC signal to be generatedon detector 26 which may be better amplified by amplifier 28. As chopper32 rotates, each hole is successively modulated for a quarter of a turn.The rotational position of chopper 32 is ascertained by a magneticpick-u head 34 which senses the passage of four small magnetic portionsof disk 32 and, accordingly, signals logic circuitry 30 so that theholes in mask 14 may be properly discriminated. Logic circuit 30 may bea stepping switch or any mechanism or circuit for supplying a signal toone of a group of indicator lights 35 each of which represents one ofthe four mask holes, when that hole is receiving radiation. For example,the magnetic impulses from pickup head 34 may be made to actuateelectronic gates which will then pass the signal from amplifier 28 tothe appropriate indicator light 35. The arrangement of these fourmagnets, mask 14, and chopper 32 may be better understood with referenceto FIGURE 2.

In FIGURE 2 is can be seen that rotation of chopper 32 about an axis 33will cause light passing through each of the four holes in mask 14 to bechopped for a quarter of a revolution. As chopper 32 is rotatedclockwise hole 16 will be chopped first followed by hole 20, hole 22,and thence hole 18. As 'mentiosed in regard to FIGURE 1 the logiccircuitry determines which of the holes is being chopped by monitoringthe passage of four magnetic inserts, shown in FIGURE 2 as inserts 36,38, 40, and 42. In the preferred embodiment of the present inventionmagnetic inserts 36, 40, and 42 are positioned near the rim of chopper32 and are detected by a first magnetic pick-up head and magnetic insert38 is positioned slightly in from the rim of chopper 32 so as to bedetected by a second magetic pick-up head. This arrangement allows logiccircuitry 30 to not only determine the beginning and end of each quarterrotation of chopper 32 but also the beginning and end of a completerevolution as signaled by the passage of magnetic insert 38. Magneticinserts 36, 38, 40 and 42 may be small bar magnets or any suitablemagnetic coating deposited on the surface of chopper 32.

It should be noted in FIGURE 2 that hole 16, the hole indicating adirect in-line target, is smaller than holes 18, and 22 which representaiming situations in which the target is led or compensated for. Thereason for this is that the procedure of compensating for a targetsspeed and distance by aiming high and in front of it is an inherentlyless accurate procedure and as such requires less exactness.Consequently, holes 18, 20 and 22 are larger so as to accept a lessaccurately aligned image and allow for more error in the aiming. Anyarrangement of holes in mask 14 may be utilized as the particularapplication requires, the size of the holes being varied to limit theaccuracy as desired.

In FIGURE 3 one possible and preferred embodiment of the presentinvention is shown. The elements in FIG- URE 3 which are the same aselements in FIGURE 1 are numbered identically. A housing 50 is shownwhich has a window therein so as to admit radiation from the target inquestion. If the simulated weapon to which housing 50 is attached iscorrectly aligned with the target radiation passes through window 25 andlens 10 in the direction indicated by a path 54. This radiation passesthrough chopper 32 and the small hole in mask 14 and is collected by theinternally reflecting cone 24 and projected onto detector 26 as alreadyexplained with reference to FIGURES 1 and 2. Chopper 32 is rotated by amotor 56 through a gear train 58. The rotation of chopper 32 ismonitored, as described before, by a magnetic recorder 34. A pair ofpick-up heads 60 and 62 are shown in FIGURE 3, head 60 detecting wholerevolutions and head 62 detectingquarter revolutions as described withreference to FIGURE 2.

If the simulated weapon to which housing 50 is attached is aimed apredetermined distance above the target in question the radiation of thetarget will enter the system along a path 64 as shown in FIGURE 3 andpass through chopper 32, one of the large holes in mask 14, and thecollecting cone 24 as already described. It should .be noted that roommay be provided for amplifier 28 and logic circuitry within the rear ofthe housing 50.

Many modifications and variations may be made to my invention by thoseskilled in the art. For example, a different optical system may beutilized to focus the image of the target onto mask 14. Also a differentform of chopper may be utilized including vibrating reeds and the like.Internally reflecting cone 24 may be replaced by a lens or othersuitable optical system which can focus the various images onto detector26. On the other hand, a single detector may be supplied for each holein mask 14 and, thus, do away with the necessity of identifying whichhole the radiation is passing through by a sequential choppingmechanism. Still another variation which may be employed is to vary thespacing of the holes in the chopper so that each hole is continuouslychopped at a different frequency and consequently each hole will have adifferent frequency of modulation. For the above reasons I do not intendthe present invention to be limited by the embodiments or structuresshown but rather only by the appended claims.

I claim:

1. An aiming evaluation device comprising:

an optical system for focusing radiant energy from a target onto a mask,said mask having a plurality of holes therein at predetermined positionscorresponding to the positions of focus of radiant energy from targetsin predetermined locations;

means for collecting the radiant energy passing through said pluralityof holes and focusing it on a detector; and

means modulating the energy passing through each of said plurality ofholes in a manner characteristic of the particular hole.

2. An optical aiming evaluation system comprising:

a lens operable to focus radiation from a target at a predeterminedpoint in a focal plane, the position of said point being a function ofthe degree of align ment of the optical system with the target;

a mask in said focal plane with a plurality of holes therein, theposition of each of the holes being such as to permit the passage ofradiation therethrough when the optical system assumes a predetermineddegree of alignment with the target;

means modulating the radiation passing through each of said holes in afashion characteristic of the particular hole;

means for collecting and projecting the radiation passing through saidplurality of holes onto a radiation detector; and

means connected to the detector for identifying the hole through whichthe radiation passed by means of the characteristic modulation.

3. An optical aiming evaluation system comprising:

a lens operable to focus radiation from a target at a predeterminedpoint in a focal plane, the position of said point being a function ofthe degree of alignment of the optical system wit-h the target;

a mask in said focal plane with a plurality of holes therein, theposition of each of the holes being such as to permit the passage ofradiation therethrough when the optical system assumes a predetermineddegree of alignment with the target;

a rotating disk chopper located in the path of the radiation proximateto the mask so as to modulate the radiation passing through each of saidholes in a fashion characteristic of the particular hole;

means for collecting and projecting the radiation passing through saidplurality of holes onto a radiation detector; and

means connected to the detector for identifying the hole through whichthe radiation passed by means of the characteristic modulation.

4. An optical aiming evaluation system comprising:

a lens operable to focus radiation from a target at a predeterminedpoint in a focal plane, the position of said point being a function ofthe degree of alignment of the optical system with the target;

a mask in said focal plane with a plurality of holes therein, theposition of each of the holes being such as to permit the passage ofradiation therethrough when the optical system assumes a predetermineddegree of alignment with the target:

means modulating the radiation passing through each of said holes in afashion characteristic of the particular hole;

an internally reflecting hollow cone for collecting and projecting theradiation passing through said plurality of holes onto a radiationdetector; and

means connected to the detector for identifying the hole through whichthe radiation passed by means of the characteristic modulation.

5. An optical aiming evaluation system comprising:

a lens operable to focus radiation from a-ta rget at a predeterminedpoint in a focal plane, the position of said point being a function ofthe degree of alignment of the optical system with the target;

a mask in said focal plane with a plurality of holes therein, theposition of each of the holes being such as to permit the passage ofradiation therethrough when the optical system assumes a predetermineddegree of alignment with the target;

a rotating disk chopper located in the path of the radiation proximateto the mask so as to modulate the radiation through each of said holesin a fashion characteristic of the particular hole;

an internally reflecting hollow cone for collecting and projecting theradiation passing through the plurality of holes onto a radiationdetector; and

logic means connected to the detector for identifying the holes throughwhich the radiation passed by means 5 6 of examining the characteristicmodulation thereradiation detecting means; from. an internallyreflecting hollow cone for collecting and 6. An optical aimingevaluation system comprising, in projecting the radiation passingthrough said plurality combination: of holes onto said radiationdetecting means; and a lens operable to focus radiation from a target ata logic circuitry means connected to the radiation detectpredeterminedpoint in a focal plane, the position of 5 ing means and the magneticpick-up head means so as said point being dependent upon the degree ofalignto determine therefrom which hole is passing the ment of theoptical system with the target; target radiation. a mask in said focalplane with a plurality of holes therein, the position of each of theholes being such References Cited as to permit the passage of radiationtherethrough 10 UNITED STATES PATENTS f :i i j ;fi Predetermmed3,083,474 4/1963 Knapp 35 -2s 3,173,019 3/1965 Wormser 250-203 Xmagnetic pick-up head means;

a rotating disk chopper located in the path of the radia- 15 tionproximate to the mask and said magnetic pick-up EUGENE R, CAPOZIO, Pri Ei e head means, said disk having chopping holes therein arranged so asto sequentially chop the radiation P. V. WILLIAMS, Assistant Examiner,passing through each hole and said rotating disk having magneticportions rotating therewith so as to indicate to the magnetic pick-uphead means which hole 20 is being chopped; 250-203; 273l01.2

